The idea here is that we should set such a high value on spiritual shrewdness and light and understanding, because that is what you get from God's word; that is what the term wisdom means. A person who does not understand God's word and what it says about the human heart and human duplicity is going to go through this life very naïvely, lacking in discernment and shrewdness.
Memorise portions of Scripture so that you can turn to them at any time and consult them when faced with difficult decisions, difficult situations. Let God’s word be as close to you as a dear sister in whom you confide. We will not let others come between us and our family members, and when temptation tries to take us away in a new direction that is liable to separate us from wisdom, we immediately sense this, and refuse to allow the family bond we have with understanding to be harmed.